COLLAPSE SIMULATION OF A FOUR-STORY STEEL MOMENT-RESISTING FRAME BY DISTRIBUTED ONLINE HYBRID TEST

摘要

The online test system, Peer-to-Peer (P2P) Internet online hybrid test system, is one of the appealing hybrid test systems developed recently. In this system, multiple substructures, either numerical or experimental, can be treated independently with only the exchange of boundary forces and displacements. The system has been demonstrated to be valid and capable of handling multiple numerical nonlinear substructures. However, its feasibility to accommodate multiple tested substructures had not been verified. To explore this possibility, a one- bay, four-story steel planar moment-resisting frame was analyzed. When the frame is subjected to extremely large earthquakes, plastic hinges form not only at the beam ends but also at the column bases where significant deterioration might occur due to the axial load. In this study, the two column bases of the frame are taken as the tested parts, while the superstructure is analyzed by ABAQUS. The three substructures are distributed to three different locations and connected through the Internet. The plastic rotations of the two column bases are treated as boundary displacements. The implicit plastic rotation is transformed to the corresponding translational displacement at the top of a cantilever column and controlled by the loading facilities. The system ran well without any malfunction and the concurrent implementation of the two tested substructures was successful, which demonstrate the feasibility and stability for the P2P system to handle multiple tested substructures involving significant resistance deterioration in part of the structure.